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+/*********************                                                        */
+/*! \file regexp_solver.h
+ ** \verbatim
+ ** Top contributors (to current version):
+ **   Andrew Reynolds, Tianyi Liang, Andres Noetzli
+ ** This file is part of the CVC4 project.
+ ** Copyright (c) 2009-2019 by the authors listed in the file AUTHORS
+ ** in the top-level source directory) and their institutional affiliations.
+ ** All rights reserved.  See the file COPYING in the top-level source
+ ** directory for licensing information.\endverbatim
+ **
+ ** \brief Regular expression solver for the theory of strings.
+ **
+ **/
+
+#include "cvc4_private.h"
+
+#ifndef CVC4__THEORY__STRINGS__REGEXP_SOLVER_H
+#define CVC4__THEORY__STRINGS__REGEXP_SOLVER_H
+
+#include <map>
+#include "context/cdhashset.h"
+#include "context/cdlist.h"
+#include "context/context.h"
+#include "expr/node.h"
+#include "theory/strings/regexp_operation.h"
+#include "util/regexp.h"
+
+namespace CVC4 {
+namespace theory {
+namespace strings {
+
+class TheoryStrings;
+
+class RegExpSolver
+{
+  typedef context::CDList<Node> NodeList;
+  typedef context::CDHashMap<Node, bool, NodeHashFunction> NodeBoolMap;
+  typedef context::CDHashMap<Node, int, NodeHashFunction> NodeIntMap;
+  typedef context::CDHashMap<Node, unsigned, NodeHashFunction> NodeUIntMap;
+  typedef context::CDHashMap<Node, Node, NodeHashFunction> NodeNodeMap;
+  typedef context::CDHashSet<Node, NodeHashFunction> NodeSet;
+
+ public:
+  RegExpSolver(TheoryStrings& p, context::Context* c, context::UserContext* u);
+  ~RegExpSolver() {}
+
+  /** add membership
+   *
+   * This informs this class that assertion is asserted in the current context.
+   * We expect that assertion is a (possibly negated) regular expression
+   * membership.
+   */
+  void addMembership(Node assertion);
+  /** check
+   *
+   * Tells this solver to check whether the regular expressions asserted to it
+   * are consistent. If they are not, then this class will call the
+   * sendInference method of its parent TheoryString object, indicating that
+   * it requires a conflict or lemma to be processed.
+   */
+  void check();
+
+ private:
+  // Constants
+  Node d_emptyString;
+  Node d_emptyRegexp;
+  Node d_true;
+  Node d_false;
+  /** the parent of this object */
+  TheoryStrings& d_parent;
+  // check membership constraints
+  Node mkAnd(Node c1, Node c2);
+  bool checkPDerivative(
+      Node x, Node r, Node atom, bool& addedLemma, std::vector<Node>& nf_exp);
+  Node getMembership(Node n, bool isPos, unsigned i);
+  unsigned getNumMemberships(Node n, bool isPos);
+  CVC4::String getHeadConst(Node x);
+  bool deriveRegExp(Node x, Node r, Node atom, std::vector<Node>& ant);
+  Node getNormalSymRegExp(Node r, std::vector<Node>& nf_exp);
+  // regular expression memberships
+  NodeList d_regexp_memberships;
+  NodeSet d_regexp_ucached;
+  NodeSet d_regexp_ccached;
+  // stored assertions
+  NodeUIntMap d_pos_memberships;
+  std::map<Node, std::vector<Node> > d_pos_memberships_data;
+  NodeUIntMap d_neg_memberships;
+  std::map<Node, std::vector<Node> > d_neg_memberships_data;
+  // semi normal forms for symbolic expression
+  std::map<Node, Node> d_nf_regexps;
+  std::map<Node, std::vector<Node> > d_nf_regexps_exp;
+  // intersection
+  NodeNodeMap d_inter_cache;
+  NodeIntMap d_inter_index;
+  // processed memberships
+  NodeSet d_processed_memberships;
+  /** regular expression operation module */
+  RegExpOpr d_regexp_opr;
+}; /* class TheoryStrings */
+
+}  // namespace strings
+}  // namespace theory
+}  // namespace CVC4
+
+#endif /* CVC4__THEORY__STRINGS__THEORY_STRINGS_H */